"BootLoader setup failed: failed to find a suitable stage1 device" error on a machine with UEFI enabled

Issue

• We saw the following error on installing Red Hat Enterprise Linux 7 on a machine with UEFI enabled.

BootLoader setup failed: failed to find a suitable stage1 device

• The relevant part of kickstart script

clearpart --drives=sda --all --initlabel
bootloader --password=xxxxxx  --iscrypted --boot-drive=sda
part efi --size=200 --ondisk=sda --fstype=efi
part /boot --size=1000 --ondisk=sda --asprimary --fstype=ext4 --label=boot --fsoptions=acl,user_xattr,errors=remount-ro,nodev,noexec,nosuid
part pv.00 --size=1 --grow --asprimary --ondisk=sda
volgroup vg00 pv.00
logvol swap --name=swap --vgname=vg00 --size=4098
logvol / --fstype=ext4 --fsoptions=acl,user_xattr,errors=remount-ro --size=1 --grow --name=root --vgname=vg00

• /tmp/anaconda.log:

11:40:37,839 DEBUG anaconda: stage1 device cannot be of type disk
11:40:37,839 DEBUG anaconda: _is_valid_disklabel(sda1) returning True
11:40:37,840 DEBUG anaconda: _is_valid_size(sda1) returning True
11:40:37,840 DEBUG anaconda: _is_valid_location(sda1) returning True
11:40:37,840 WARN anaconda: sda1 not bootable
11:40:37,841 DEBUG anaconda: _is_valid_format(sda1) returning False
11:40:37,841 DEBUG anaconda: is_valid_stage1_device(sda1) returning False
11:40:37,842 DEBUG anaconda: _is_valid_disklabel(sda2) returning True
11:40:37,842 DEBUG anaconda: _is_valid_size(sda2) returning True
11:40:37,842 DEBUG anaconda: _is_valid_location(sda2) returning True
11:40:37,843 DEBUG anaconda: _is_valid_format(sda2) returning False
11:40:37,843 DEBUG anaconda: is_valid_stage1_device(sda2) returning False
11:40:37,844 DEBUG anaconda: _is_valid_disklabel(sda3) returning True
11:40:37,844 DEBUG anaconda: _is_valid_size(sda3) returning True
11:40:37,844 DEBUG anaconda: _is_valid_location(sda3) returning True
11:40:37,845 WARN anaconda: sda3 not bootable
11:40:37,845 DEBUG anaconda: _is_valid_format(sda3) returning False
11:40:37,845 DEBUG anaconda: is_valid_stage1_device(sda3) returning False
11:40:37,846 DEBUG anaconda: stage1 device cannot be of type lvmvg
11:40:37,846 DEBUG anaconda: stage1 device cannot be of type lvmlv
11:40:37,846 DEBUG anaconda: stage1 device cannot be of type lvmlv
11:40:37,847 ERR anaconda: BootLoader setup failed: failed to find a suitable stage1 device